Post-stroke Hemiparetic Patients Research Articles

Transcultural translation and validation of Fugl–Meyer assessment to Italian

Purpose The Fugl–Meyer Assessment is the most used and highly recommended clinical assessment of sensorimotor function after stroke. A standardized use of the scale in different countries requires translation and cultural validation to the target language. The objective of the study was to develop an official Italian version of the scale by transcultural translation and validation. Methods A standardized multistep translation protocol was adopted to achieve optimal conceptual and semantic equivalence. The developed Italian version was validated in 10 post-stroke hemiparetic patients. Items with low intra- and interrater agreement, quantified as percentage of agreement <70% and/or statistically significant disagreement in relative position or concentration, between different raters were identified and revised. Results All motor items received a high level of agreement with values well above 70%. Disagreements were observed in 6 items in the sensory, joint range and pain domains and 1 in one reflex item. Items showing disagreements were discussed and revised to establish the final Italian version. Conclusions The culturally validated Italian Fugl–Meyer Assessment can reliably be used in research and in clinical practice. A standardized use will improve the quality of sensorimotor assessment in stroke across Italy and allow reliable comparisons of stroke populations internationally. Implications for rehabilitation The Fugl–Meyer Assessment is the gold standard for evaluation of sensorimotor impairment after stroke. Having access to a transculturally validated official Italian version of Fugl–Meyer Assessment will improve the quality of sensorimotor assessment after stroke among Italian health professionals and researchers. A wider standardized use of the Fugl–Meyer Assessment in Italy will allow reliable international comparison of stroke rehabilitation outcomes.

Quantitative Assessment of Upper-Limb Motor Function for Post-Stroke Rehabilitation Based on Motor Synergy Analysis and Multi-Modality Fusion.

Functional assessment is an essential part of rehabilitation protocols after stroke. Conventionally, the assessment process relies heavily on clinical experience and lacks quantitative analysis. In order to objectively quantify the upper-limb motor impairments in patients with post-stroke hemiparesis, this study proposes a novel assessment approach based on motor synergy quantification and multi-modality fusion. Fifteen post-stroke hemiparetic patients and fifteen age-matched healthy persons participated in this study. During different goal-directed tasks, kinematic data and surface electromyography(sEMG) signals were synchronously collected from these participants, and then motor features extracted from each modal data could be fed into the respective local classifiers. In addition, kinematic synergies and muscle synergies were quantified by principal component analysis (PCA) and k weighted angular similarity ( k WAS) algorithm to provide in-depth analysis of the coactivated features responsible for observable movement impairments. By integrating the outputs of local classifiers and the quantification results of motor synergies, ensemble classifiers can be created to generate quantitative assessment for different modalities separately. In order to further exploit the complementarity between the evaluation results at kinematic and muscular levels, a multi-modal fusion scheme was developed to comprehensively analyze the upper-limb motor function and generate a probability-based function score. Under the proposed assessment framework, three types of machine learning methods were employed to search the optimal performance of each classifier. Experimental results demonstrated that the classification accuracy was respectively improved by 4.86% and 2.78% when the analysis of kinematic and muscle synergies was embedded in the assessment system, and could be further enhanced to 96.06% by fusing the characteristics derived from different modalities. Furthermore, the assessment result of multi-modality fusion framework exhibited a significant correlation with the score of standard clinical tests ( R = - 0.87, P = 1.98e - 5 ). These promising results show the feasibility of applying the proposed method to clinical assessments for post-stroke hemiparetic patients.

Gait characteristics of post-stroke hemiparetic patients with different walking speeds.

Hemiparesis resulting from stroke presents characteristic spatiotemporal gait patterns. This study aimed to clarify the spatiotemporal gait characteristics of hemiparetic patients by comparing them with height-, speed-, and age-matched controls while walking at various speeds. The data on spatiotemporal gait parameters of stroke patients and that of matched controls were extracted from a hospital gait analysis database. In total, 130 pairs of data were selected for analysis. Patients and controls were compared for spatiotemporal gait parameters and the raw value (RSI) and absolute value (ASI) of symmetry index and coefficient of variation (CV) of these parameters. Stroke patients presented with prolonged nonparetic stance (patients vs. controls: 1.01 ± 0.41 vs. 0.83 ± 0.25) and paretic swing time (0.45 ± 0.12 vs. 0.39 ± 0.07), shortened nonparetic swing phase (0.35 ± 0.07 vs. 0.39 ± 0.07), and prolonged paretic and nonparetic double stance phases [0.27 ± 0.13 (paretic)/0.27 ± 0.17 (nonparetic) vs. 0.22 ± 0.10]. These changes are especially seen in low-gait speed groups (<3.4 km/h). High RSIs of stance and swing times were also observed (–9.62 ± 10.32 vs. –0.79 ± 2.93, 24.24 ± 25.75 vs. 1.76 ± 6.43, respectively). High ASIs and CVs were more generally observed, including the groups with gait speed of ≥3.5 km/h. ASI increase of the swing phase (25.79 ± 22.69 vs. 4.83 ± 4.88) and CV of the step length [7.7 ± 4.9 (paretic)/7.6 ± 5.0 (nonparetic) vs. 5.3 ± 3.0] were observed in all gait speed groups. Our data suggest that abnormalities in the spatiotemporal parameters of hemiparetic gait should be interpreted in relation to gait speed. ASIs and CVs could be highly sensitive indices for detecting gait abnormalities.

Percepção da qualidade de vida de pacientes hemiparéticos pós-acidente vascular cerebral em um grupo de equilíbrio em ambiente aquático

OBJETIVO: Avaliar a percepção da qualidade de vida de pacientes hemiparéticos pós acidente vascular cerebral (AVC) submetidos a um protocolo de equilíbrio em grupo em ambiente aquático.MÉTODOS: Cinco pacientes hemiparéticos pós-AVC foram submetidos a protocolo de equilíbrio em grupo em ambiente aquático, em 24 sessões, realizadas duas vezes por semana, com duração de uma hora cada sessão. A amostra foi avaliada antes e imediatamente após o protocolo utilizando a Escala de Equilíbrio de Berg (EEB), o teste Timed Up and Go (TUG) e a Escala de Qualidade de Vida Específica para Acidente Vascular Encefálico (EQVE-AVE). As variáveis pré e pós-tratamento foram analisadas por meio do teste t de Student para amostras pareadas, com significância de p&lt;0,05.RESULTADOS: Houve melhora da mobilidade e segurança avaliada por meio do TUG (p&lt;0,01) e melhora da percepção da qualidade de vida avaliada por meio da EQVE-AVE (p&lt;0,05) em todos os indivíduos no período pós-tratamento.CONCLUSÕES: Os indivíduos apresentaram melhora da percepção da qualidade de vida, do equilíbrio e marcha após protocolo de equilíbrio realizado em grupo em ambiente aquático.

Brain-Machine Interface-Driven Post-Stroke Upper-Limb Functional Recovery Correlates With Beta-Band Mediated Cortical Networks.

Brain-machine interface (BMI)-driven robot-assisted neurorehabilitation intervention has demonstrated improvement in upper-limb (UL) motor function, specifically, with post-stroke hemiparetic patients. However, neurophysiological patterns related to such interventions are not well understood. This paper examined the longitudinal changes in band-limited resting-state (RS) functional connectivity (FC) networks in association with post-stroke UL functional recovery achieved by a multimodal intervention involving motor attempt (MA)-based BMI and robotic hand-exoskeleton. Four adults were rehabilitated with the intervention for a period lasting up to six weeks. RS magnetoencephalography (MEG) signals, Action Research Arm Test (ARAT), and grip strength (GS) measures were recorded at five equispaced sessions over the intervention period. An average post-interventional increase of 100.0% (p=0.00028) and 88.0% was attained for ARAT and GS, respectively. A cluster-based statistical test involving correlation estimates between beta-band (15-26 Hz) RS-MEG FCs and UL functional recovery provided the positively correlated sub-networks in both the contralesional and ipsilesional motor cortices. The frontoparietal FC exhibited hemispheric lateralization wherein the majority of the positively and negatively correlated connections were found in contralesional and ipsilesional hemispheres, respectively. Our findings are consistent with the theory of bilateral motor cortical association with UL recovery and predict novel FC patterns that can be important for higher level cognitive functions.

Lokomat guided gait in hemiparetic stroke patients: the effects of training parameters on muscle activity and temporal symmetry

Purpose: The Lokomat is a commercially available robotic gait trainer, applied for gait rehabilitation in post-stroke hemiparetic patients. Selective and well-dosed clinical use of the Lokomat training parameters, i.e. guidance, speed and bodyweight support, requires a good understanding of how these parameters affect the neuromuscular control of post-stroke hemiparetic gait.Materials and methods: Ten stroke patients (unilateral paresis, 7 females, 64.5 ± 6.4 years, >3months post-stroke, FAC scores 2–4)) walked in the Lokomat under varying parameter settings: 50% or 100% guidance, 0.28 or 0.56m/s, 0% or 50% bodyweight support. Electromyography was recorded bilaterally from Gluteus Medius, Biceps Femoris, Vastus Lateralis, Medial Gastrocnemius, and Tibialis Anterior. Pressure sensors placed under the feet were used to determine the level of temporal gait symmetry.Results: Varying guidance and bodyweight support had little effect on muscle activity, but increasing treadmill speed led to increased activity in both the affected (Biceps Femoris, Medial Gastrocnemius, Tibialis Anterior) and unaffected leg (all muscles). The level of temporal symmetry was unaffected by the parameter settings.Conclusions: The Lokomat training parameters are generally ineffective in shaping short term muscle activity and step symmetry patients with hemiparetic stroke, as speed is the only parameter that significantly affects muscular amplitude.Trial Registration: d.n.a.IMPLICATIONS FOR REHABILITATIONThe Lokomat is a commercially available gait trainer that can be used for gait rehabilitation in post-stroke hemiparetic patients.This study shows that muscle amplitude is generally low during Lokomat guided walking, and that treadmill Speed is the main training parameter to influence muscular output in stroke patients during Lokomat walking.Varying Guidance and Bodyweight Support within a clinical relevant range barely affected muscle activity, and temporal step symmetry was unaffected by variation in any of the training parameters.Based on the findings it is advised to increase speed as early as possible during Lokomat therapy, or use other means (e.g. feedback or instructions) to stimulate active involvement of patients during training.

Low-Cost Tracking Systems Allow Fine Biomechanical Evaluation of Upper-Limb Daily-Life Gestures in Healthy People and Post-Stroke Patients.

Since the release of the first Kinect in 2011, low-cost technologies for upper-limb evaluation has been employed frequently for rehabilitation purposes. However, a limited number of studies have assessed the potential of the Kinect V2 for motor evaluations. In this paper, a simple biomechanical protocol has been developed, in order to assess the performances of healthy people and patients, during daily-life reaching movements, with focus on some of the patients’ common compensatory strategies. The assessment considers shoulder range of motion, elbow range of motion, trunk compensatory strategies, and movement smoothness. Seventy-seven healthy people and twenty post-stroke patients participated to test the biomechanical assessment. The testing protocol included four different experimental conditions: (1) dominant limb and (2) non-dominant limb of 77 healthy people, and (3) the more impaired limb of 20 post-stroke hemiparetic patients, and (4) the less-impaired limb of 11 patients (subgroup of the original 20). Biomechanical performances of the four groups were compared. Results showed that the dominant and non-dominant limbs of healthy people had comparable performances (p > 0.05). On the contrary, condition (3) showed statistically significant differences between the healthy dominant/non-dominant limb and the less-affected limb in hemiparetic patients, for all parameters of assessment (p < 0.001). In some cases, the less-affected limb of the patients also showed statistical differences (p < 0.05), with respect to the healthy people. Such results suggest that Kinect V2 has the potential for being employed at home, laboratory or clinical environment, for the evaluation of patients’ motor performances.

Correlation analysis of motor function improvement and brain structure for upper limb paralysis.

Intervention with combined low-frequency repetitive transcranial magnetic stimulation and intensive occupational therapy can improve brain function in poststroke patients with motor paralysis. We aimed to evaluate the relationship between brain structure at the time of intervention and the degree of motor function improvement using this combination therapy. Twenty-five patients with upper limb paralysis after stroke were hospitalized for 15 days to receive 12 sessions of low-frequency repetitive transcranial magnetic stimulation over the nonlesional hemisphere and occupational therapy. Imaging analysis was carried out using three-dimensional T1-weighted images. Correlation analysis between cortical thickness and upper limb motor function score was carried out using FreeSurfer. Correlation analysis between cortical thickness and motor function improvement was carried out by atlas-based analysis. FreeSurfer showed that significant positive correlations were found between cortical thickness of the postcentral or supramarginal gyrus of the diseased hemisphere and motor function improvements in nondominant hand paralysis (uncorrected P<0.001). Results using the atlas supported these results (P<0.05). The results of the analysis indicated that the effect of our proposed treatment could be related to the cortical thickness. In particular, it is considered that the cortical thickness of the postcentral gyrus or the supramarginal gyrus of the affected hemisphere plays an important role in such recovery in poststroke hemiparetic patients.

Muscle force strategies for poststroke hemiparetic patients during gait

ABSTRACTBackground and Objective: Individuals who survive a stroke often display considerable gait impairments that occur in part due to inadequate muscle force production. This study aimed to investigate lower limb muscle forces in poststroke patients during walking.Methods: Kinematics, kinetics, and electromyographic (EMG) measurements were performed on nine poststroke and healthy individuals walking at natural speed in a cross-sectional study. Recorded parameters were used in an EMG-driven model to estimate the forces exerted by the muscles around the knee and ankle joints during the stance (braking and propulsion) and swing phases.Results: For hemiparetic patients, in comparison to healthy controls, the paretic side exhibited (i) lower forces generated by plantar-flexors and quadriceps respectively during the braking and propulsion phases, but (ii) higher knee-flexors forces during the propulsion phase. Regarding the non-paretic side, it displayed (i) higher forces generated by knee-flexors and quadriceps (only for the propulsion phase) forces during the stance phase, and (iii) higher plantar-flexors forces during the swing phase, in comparison to controls.Conclusion: Reduced forces exerted by the plantar-flexors and the knee-extensors along with increased force generated by the knee-flexors on the paretic side give possible explanation for hemiparetic gait abnormalities. Increased muscle forces exerted by the non-paretic side might be a compensatory strategy to better support body weight and properly adjust the center of mass forward.

Kinematic Parameters for Changing From Sitting to Standing Position and Gait in Poststroke Hemiparetic Patients

Hemiparetic individuals present changes that negatively affect the functional activities. The purpose of this article is to identify the kinematic parameters in poststroke hemiplegic patients for the duration of changing from the sitting to standing position and then to walking. Sociodemographic and clinical data were collected on the severity of stroke by using the National Institutes of Health Stroke Scale; functional mobility, by the Timed Up and Go test; and the kinematic parameters of changing from the sitting to standing position and then walking by means of the free Computation Vision Mobility software program. There was statistical difference in hip extension associated with ankle dorsiflexion in the final stage of support for walking and dorsiflexion in the beginning (P = .04) and while changing from the sitting to standing position (P = .01), speed (P &lt; .01), cadence (P = .03), and step/stride length (P &lt; .01) of gait. Significant correlations were found between cadence (r 2 = 0.72), speed (r 2 = 0.87), and step/stride length (r 2 = 0.71) and compromised functional mobility. Individuals with hemiparesis after stroke who presented greater ankle dorsiflexion when moving to standing performed a hip extension and dorsiflexion of the ankle in the final support of gait. Individuals who presented this position at this stage of walking had adequate temporal-spatial gait parameters, and these parameters showed significant correlations with impaired functional mobility.

EFFECTIVENESS OF VIRTUAL REALITY IN RECOVERY OF MOTOR FUNCTION IN POST-STROKE HEMIPARESIS: A QUASI-EXPERIMENTAL STUDY

Virtual Reality(VR) is a novel treatment approach for stroke rehabilitation as it enables individuals to reproduce standard controlled movements to accomplish functional task. In contrast to conventional rehabilitation that is monotonous, long-term and challenging, VR increases patient interest in rehabilitation thereby reduces the boredom and adaptation therefore enhances the visuo-spatial feedback. It has been observed that approximately 65% of the stroke survivors suffer hemiparesis that predominantly leads difficulty in performing daily living activities. Therefore, this study aims to assess the sensorimotor and functional performance in post-stroke hemiparetic patients using VR based gaming system. A total of 81 participants who had first-ever ischemic or hemorrhagic stroke with onset of &gt;6 months, enrolled in post-acute rehabilitation program at Tertiary Care Hospital were included. The VR gaming software named Wonder Tree (WT) © was used for the intervention. All participants were required to play two different games i.e. bucket ball and bubble pop for 15-20 minutes, 3 days/week for the duration of 8th weeks. Participants were assessed on baseline and post-intervention on Fugyl-Meyer Assessment for Upper Extremity (FMA-UE) and Wolf Motor Function Test (W.MFT) to assess sensorimotor function and functional skills. Participants showed significant improvement in sensorimotor function and functional abilities (p&lt;0.05) after 8th weeks of intervention.

Prediction of the oxygen cost of walking in hemiparetic stroke patients

The energy cost of walking is a marker of metabolic solicitation and allows energy quantification of walking. It is strongly correlated to the patient's walking speed with post-stroke sequelae. We wanted to develop a model for predicting the energy cost of walking to create of walking distance recommendations aimed at achieving recommended energy expenditure levels to ensure health benefits (> 1000 kcal/week during physical activities). To verify the close relationship between spontaneous walking speed (S free ) and energy cost of walking at S free (Cw free ) in subjects with post-stroke hemiparetic patients sequelea and to test the validity of a prediction model to estimate Cw free based on S free . Twenty-six mild to moderately disabled chronic participants with stroke aged 65 yrs (± 15.7yrs) walked at S free using mobility aids if necessary, for 6 minutes. The Cw free was measured at a stabilized metabolic rate by indirect calorimetry using the Metamax3B device. The relationship between S free and Cw free was analyzed using the correlation coefficient, coefficient of determination. The Cw free prediction model was developed from a regression equation and then tested on a new population with the same inclusion/exclusion criteria ( n = 29). S free and Cw free had a correlation coefficient of −0.94 and a R 2 of 0.97 enabling to formulate a regression equation and develop the Cw free prediction model based on S free . The prediction model tests yielded accurate results with a mean bias of −0.02 mL.kg −1 .m −1 –MD% = 4%. The limits of agreement were −0.31; 0.26 mL.kg −1 .m −1 MD% = 30.9% of the mean measured Cw free . Cw free can be estimated precisely by a simple measurement of the walking speed. In this way, we can easily define the distance the subject must travel according to his Cw to reach the recommended energy expenditure targets. It is a great help for the practitioner for recommendations in the field of physical activity after stroke.

Simultaneous Recognition and Assessment of Post-Stroke Hemiparetic Gait by Fusing Kinematic, Kinetic, and Electrophysiological Data.

Gait analysis for the patients with lower limb motor dysfunction is a useful tool in assisting clinicians for diagnosis, assessment, and rehabilitation strategy making. Implementing accurate automatic gait analysis for the hemiparetic patients after stroke is a great challenge in clinical practice. This study is to develop a new automatic gait analysis system for qualitatively recognizing and quantitatively assessing the gait abnormality of the post-stroke hemiparetic patients. Twenty-one post-stroke patients and twenty-one healthy volunteers participated in the walking trials. Three of the most representative gait data, i.e., marker trajectory (MT), ground reaction force (GRF), and electromyogram, were simultaneously acquired from these subjects during their walking. A multimodal fusion architecture is established by using these different modal data to qualitatively distinguish the hemiparetic gait from normal gait by different pattern recognition techniques and to quantitatively estimate the patient's lower limb motor function by a novel probability-based gait score. Seven decision fusion algorithms have been tested in this architecture, and extensive data analysis experiments have been conducted. The results indicate that the recognition performance and estimation performance of the system become better when more modal gait data are fused. For the recognition performance, the random forest classifier based on the GRF data achieves an accuracy of 92.26% outperformed other single-modal schemes. When combining two modal data, the accuracy can be enhanced to 95.83% by using the support vector machine (SVM) fusion algorithm to fuse the MT and GRF data. When integrating all the three modal data, the accuracy can be further improved to 98.21% by using the SVM fusion algorithm. For the estimation performance, the absolute values of the correlation coefficients between the estimation results of the above three schemes and the Wisconsin gait scale scores for the post-stroke patients are 0.63, 0.75, and 0.84, respectively, which means the clinical relevance becomes more obvious when using more modalities. These promising results demonstrate that the proposed method has considerable potential to promote the future design of automatic gait analysis systems for clinical practice.

Predicting the oxygen cost of walking in hemiparetic stroke patients.

To verify the relation between spontaneous walking speed (Sfree) and oxygen cost of walking at Sfree (Cwfree) in post-stroke hemiparetic patients and to test the validity of a prediction model to estimate Cwfree based on Sfree. We included 26 participants (mean age 65.1 years [SD 15.7]) with mild to moderate disability after stroke who walked at Sfree using mobility aids if necessary for 6min. The Cwfree was measured at a stabilized metabolic rate by indirect calorimetry with the Metamax 3B spiroergometry device. The relation between Sfree and Cwfree was analyzed by the correlation coefficient (r) and coefficient of determination (R2). The Cwfree prediction model was developed from a regression equation, then tested on a second population of 29 patients (mean age 62.1 years [SD 13.4]) with the same inclusion and exclusion criteria. For the 26 participants, the Sfree and Cwfree were highly correlated (r=-0.94 and R2=0.97), which allowed for formulating a regression equation and developing the Cwfree prediction model based on Sfree. The prediction model tests yielded accurate results (mean bias -0.02mL.kg-1.m-1; 95% limits of agreement -0.31 to 0.26mL.kg-1.m-1). The relation between Cwfree estimated by the model and measured by Metamax was high (R2=0.98). Cwfree was strongly correlated with Sfree, which allowed for the development of a valid Cwfree prediction model. A practitioner could estimate the energy expenditure of walking for a patient without using an indirect calorimeter.

Optimizing a Treadmill Ramp Protocol to Evaluate Aerobic Capacity of Hemiparetic Poststroke Patients.

Bernardes, WL, Montenegro, RA, Monteiro, WD, de Almeida Freire, R, Massaferri, R, and Farinatti, P. Optimizing a treadmill ramp protocol to evaluate aerobic capacity of hemiparetic poststroke patients. J Strength Cond Res 32(3): 876-884, 2018-A correct assessment of cardiopulmonary capacity is important for aerobic training within motor rehabilitation of poststroke hemiparetic patients (PSHPs). However, specific cardiopulmonary exercise testing (CPET) for these patients are scarce. We proposed adaptations in a protocol originally developed for PSHPs by Ovando et al. (CPET1). We hypothesized that our adapted protocol (CPET2) would improve the original test, by preventing early fatigue and increasing patients' peak performance. Eleven PSHPs (52 ± 14 years, 10 men) performed both protocols. CPET2 integrated changes in final speed (100-120% vs. 140% maximal speed in 10-m walking test), treadmill inclination (final inclination of 5 vs. 10%), and estimated test duration (10 vs. 8 minutes) to smooth the rate of workload increment of CPET1. Peak oxygen uptake (V[Combining Dot Above]O2peak) (20.3 ± 6.1 vs. 18.6 ± 5.0 ml·kg·min; p = 0.04), V[Combining Dot Above]O2 at gas exchange transition (V[Combining Dot Above]O2-GET) (11.5 ± 2.9 vs. 9.8 ± 2.0 ml·kg·min; p = 0.04), and time to exhaustion (10 ± 3 vs. 6 ± 2 minutes; p < 0.001) were higher in CPET2 than in CPET1. Slopes and intercepts of regressions describing relationships between V[Combining Dot Above]O2 vs. workload, heart rate vs. workload, and V[Combining Dot Above]O2 vs. heart rate were similar between CPETs. However, standard errors of estimates obtained for regressions between heart rate vs. workload (3.0 ± 1.3 vs. 3.8 ± 1.0 b·min; p = 0.004) and V[Combining Dot Above]O2 vs. heart rate (6.0 ± 2.1 vs. 4.8 ± 2.4 ml·kg·min; p = 0.05) were lower in CPET2 than in CPET1. In conclusion, the present adaptations in Ovando's CPET protocol increased exercise tolerance of PSHPs, eliciting higher V[Combining Dot Above]O2peak and V[Combining Dot Above]O2-GET, preventing earlier fatigue, and providing better physiological relationships along submaximal workloads.

Influence of manual dominance on the uni- and bi-manual activities of post-stroke patients treated with constraint-induced therapy

Background: Constraint-induced therapy (CIT) has long-term beneficial effects. However, there is evidence that the recovery of the functional movements of the affected hand can be influenced by hand dominance prior to the brain injury and that this aspect may influence the maintenance of the CIT results. Aim: To investigate the influence of previous hand dominance in post-stroke hemiparetic patients on immediate CIT results and result maintenance in uni- and bi-manual activities for at least 12 months. Methods: This study was an observational study that used medical records of patients who performed the CIT protocol between 2009 and 2014. Thirty-four patients were included and divided into two groups [concordance group (n=18; age: 56(13); sex: 11 male) and non-dominant group (n=16; age: 57(13); sex: 9 male)]. Two scales were used: the Motor Activity Log (MAL), and the Wolf Motor Function Test (WMFT). Results: MAL and WMFT scales showed significant improvement comparing pre- to post-treatment. However, there is no statistical difference between the groups and the follow-ups on both scales. Conclusions: There was significant improvement and maintenance in both the quality and the amount of use in the more affected upper limb, but the previous manual dominance was not a relevant factor.

Combining muscle synergies and biomechanical analysis to assess gait in stroke patients.

The understanding of biomechanical deficits and impaired neural control of gait after stroke is crucial to prescribe effective customized treatments aimed at improving walking function. Instrumented gait analysis has been increasingly integrated into the clinical practice to enhance precision and inter-rater reliability for the assessment of pathological gait. On the other hand, the analysis of muscle synergies has gained relevance as a novel tool to describe the neural control of walking. Since muscle synergies and gait analysis capture different but equally important aspects of walking, we hypothesized that their combination can improve the current clinical tools for the assessment of walking performance. To test this hypothesis, we performed a complete bilateral, lower limb biomechanical and muscle synergies analysis on nine poststroke hemiparetic patients during overground walking. Using stepwise multiple regression, we identified a number of kinematic, kinetic, spatiotemporal and synergy-related features from the paretic and non-paretic side that, combined together, allow to predict impaired walking function better than the Fugl-Meyer Assessment score. These variables were time of peak knee flexion, VAFtotal values, duration of stance phase, peak of paretic propulsion and range of hip flexion. Since these five variables describe important biomechanical and neural control features underlying walking deficits poststroke, they may be feasible to drive customized rehabilitation therapies aimed to improve walking function. This paper demonstrates the feasibility of combining biomechanical and neural-related measures to assess locomotion performance in neurologically injured individuals.

Walking speed intention model using soleus electromyogram signal of nondisabled and post-stroke hemiparetic patients.

It is well known that the activation of plantar flexors have a strong influence on the walking speed. If the gait speed can be predicted using this relationship, a post-stroke hemiparetic patient could control a gait rehabilitation robot according to his or her gait intention, and the robotic gait rehabilitation effect could be further improved. To find out this relationship, 9 nondisabled subjects and 4 chronic post-stroke hemiparetic subjects performed overground level walking at a comfortable pace, a slow pace, a fast pace, and an increasing pace with electromyogram sensors attached on plantar flexors. Soleus among plantar flexors showed the most stable relationship with walking speed. The relationship between maximum activation level of soleus electromyogram during stance phase before toe-off and walking speed during swing phase after the same toe-off was modeled by a polynomial regression model. The model outputs were then compared to the measured walking speeds using coefficients of determination (R2). The average R2 values are 0.594 and 0.692 for 1st· and 2nd order models respectively in the nondisabled subjects. The average R2 values are 0.598 and 0.623 for the unaffected side and 0.388 and 0.394 for the affected side in the chronic subjects. The results show the feasibility of applying the soleus-walking speed relationship to control the robot gait speed at will. A walking speed estimation method is proposed using only a walking step in real time.

Observational Study of 180° Turning Strategies Using Inertial Measurement Units and Fall Risk in Poststroke Hemiparetic Patients.

We analyzed spontaneous 180° turning strategies in poststroke hemiparetic patients by using inertial measurement units (IMUs) and the association of turning strategies with risk of falls. We included right paretic (RP) and left paretic (LP) post-stroke patients, and healthy controls (HCs) from a physical and rehabilitation department in France between July 2015 and October 2015. All subjects were right-handed and right-footed for mobilization tasks. Participants were instructed to turn 180° in a self-selected direction after a 10-m walk while wearing three IMUs on their trunk and both feet. We defined three turning patterns based on the number of external steps (pattern I = 1; II = 2-4 steps; and III ≥ 5) and four turning strategies based on the side chosen to turn (healthy or paretic) and the stance limb used during the first step of the turn (healthy or paretic). Falls in the 6 months after measurement were investigated. We included 17 RP [mean (SD) age 57.5 (9.5) years (range 43-73)], 20 LP patients [mean age 60.7 (8.8) years (range 43-63)], and 15 HCs [mean age 56.7 (16.1) years (range 36-83)]. The LP and RP groups behaved similarly in turning patterns, but 90% of LP patients turned spontaneously to the paretic side versus 59% of RP patients. This difference increased with turning strategies: 85% of LP versus 29% of RP patients used strategy 4 (paretic turn side with paretic limb). Patients using strategy 4 had the highest rate of falls. We propose to consider spontaneous turning strategies as new indicators to evaluate the risk of fall after stroke. IMU could be routinely used to identify this risk and guide balance rehabilitation programs.

Differences in muscle activity and temporal step parameters between Lokomat guided walking and treadmill walking in post-stroke hemiparetic patients and healthy walkers

BackgroundThe Lokomat is a robotic exoskeleton that can be used to train gait function in hemiparetic stroke. To purposefully employ the Lokomat for training, it is important to understand (1) how Lokomat guided walking affects muscle activity following stroke and how these effects differ between patients and healthy walkers, (2) how abnormalities in the muscle activity of patients are modulated through Lokomat guided gait, and (3) how temporal step characteristics of patients were modulated during Lokomat guided walking.MethodsTen hemiparetic stroke patients (>3 months post-stroke) and ten healthy age-matched controls walked on the treadmill and in the Lokomat (guidance force 50%, no bodyweight support) at matched speeds (0.56 m/s). Electromyography was used to record the activity of Gluteus Medius, Biceps Femoris, Vastus Lateralis, Medial Gastrocnemius and Tibialis Anterior, bilaterally in patients and of the dominant leg in healthy walkers. Pressure sensors placed in the footwear were used to determine relative durations of the first double support and the single support phases.ResultsOverall, Lokomat guided walking was associated with a general lowering of muscle activity compared to treadmill walking, in patients as well as healthy walkers. The nature of these effects differed between groups for specific muscles, in that reductions in patients were larger if muscles were overly active during treadmill walking (unaffected Biceps Femoris and Gluteus Medius, affected Biceps Femoris and Vastus Lateralis), and smaller if activity was already abnormally low (affected Medial Gastrocnemius). Also, Lokomat guided walking was associated with a decrease in asymmetry in the relative duration of the single support phase.ConclusionsIn stroke patients, Lokomat guided walking results in a general reduction of muscle activity, that affects epochs of overactivity and epochs of reduced activity in a similar fashion. These findings should be taken into account when considering the clinical potential of the Lokomat training environment in stroke, and may inform further developments in the design of robotic gait trainers.